The screening effects of the electrons in the filled K- shell, L-subshells and M-subshells are
represented by an effective nuclear charge of the form \(Z_{\mathrm {eff}}=Z-s_{i}\) ,
a procedure that should be reasonable for small principal quantum number \(n\)  and small
\(n-l\)  [1]}. These screening constants \(s_{i}\)  are taken from the
fits [2]} of Dirac single electron eigenfunctions to empirical binding energies.
For neon, they are
2.016 (K-shell), 6.254 (L\(_{\mathrm {I}}\)  -subshell), and 7.482 (L\(_{\mathrm {II}}\) - and
L\(_{\mathrm {III}}\) - subshells).
For argon, the constants are
2.721 (K-shell), 8.248 (L\(_{\mathrm {I}}\)  -subshell),
9.470 (L\(_{\mathrm {II}}\) - and L\(_{\mathrm {III}}\) - subshells),
13.603 (M\(_{\mathrm {I}}\)  -subshell), and 14.771 (L\(_{\mathrm {II}}\) - and L\(_{\mathrm {III}}\) - subshells).
